fingerd

FINGERD(8) BSD System Manager’s Manual FINGERD(8)

NAME

fingerd - remote user information server

SYNOPSIS

fingerd [-wulf] [-pLpath] [-ttimeout]

DESCRIPTION

Fingerd is a simple daemon based on RFC1196 that provides an interface to
the “finger” program at most network sites. The program is supposed to
return a friendly, human-oriented status report on either the system at
the moment or a particular person in depth.
If the -w option is given, remote users will get an additional “Welcome
to ...” banner which also shows some informations (e.g. uptime, operating
system name and release) about the system the fingerd is running on. Some
sites may consider this a security risk as it gives out information that
may be useful to crackers.
If the -u option is given, requests of the form “finger @host” are
rejected.
If the -l option is given, information about requests made is logged.
This option probably violates users’ privacy and should not be used on
multiuser boxes.
If the -f option is given, finger forwarding (user@host1@host2) is
allowed. Useful behind firewalls, but probably not wise for security and
resource reasons.
The -p option allows specification of an alternate location for fingerd
to find the “finger” program. The -L option is equivalent.
The -t option specifies the time to wait for a request before closing the
connection. A value of 0 waits forever. The default is 60 seconds.
Options to fingerd should be specified in /etc/xinetd.d/finger.
The finger protocol consists mostly of specifying command arguments. The
xinetd(8) “super-server” runs fingerd for TCP requests received on port
79. Once connected fingerd reads a single command line terminated by a
〈CRLF〉 which is passed to finger(1). It closes its connections as soon
as all output is finished.
If the line is empty (i.e. just a 〈CRLF〉 is sent) then finger returns a
“default” report that lists all people logged into the system at that
moment. This feature is blocked by the -u option.
If a user name is specified (e.g. eric〈CRLF〉) then the response lists
more extended information for only that particular user, whether logged
in or not. Allowable “names” in the command line include both “login
names” and “user names”. If a name is ambiguous, all possible deriva-
tions are returned.

SEE ALSO

finger(1), xinetd(8)

RESTRICTIONS

Connecting directly to the server from a TIP or an equally narrow-minded
TELNET-protocol user program can result in meaningless attempts at option
negotiation being sent to the server, which will foul up the command line
interpretation.